1. Field of the Invention
This invention relates to disposable single-use devices, which can be, for example, electronic surgical apparatus such as an electrosurgical or electrocautery device. In particular, this invention relates to such devices that include a thermal switch configured to electronically disable a single-use apparatus so that it cannot be used a second time.
2. Background of the Invention
Medical devices such as, for example, electrosurgery and electrocautery devices, may be used to, for example, cut living organic tissue. The cutting action is accomplished by inserting a distal end of the device into the tissue. These devices may also be used to cauterize tissue surrounding the distal end of the device, thereby coagulating blood in the surrounding tissue.
Over time, the requirements to maintain a sterile operating field during the use of such medical devices have become more stringent. This has led to a great number of medical devices such as, for example, electrosurgical or electrocautery devices, being manufactured as single use disposable items, rather than items that are resterilized and reused. In addition to reducing the transmission of organisms and infectious agents, this change has also led to surgical products performing more reliably and consistently. Reusable products that are sometimes old, often cleaned properly, often repaired properly, but always with a different history will always be less reliable and consistent than new, essentially identical products. For this reason, many medical devices are manufactured with the intent that they will be used a single time. Device manufacturers also do testing that very accurately characterizes performance of a device over a limited life span that is impossible over an extended life span.
A disadvantage of the change to single-use disposable items is that the cost of any medical procedure is increased. In response to this increased cost, some medical facilities have begun reusing medical devices that were designed for one use. For the medical facility, the cost of a procedure will drop while reimbursement stays the same. However, the patient bears an additional risk of transmittable disease and the physician bears additional risk of liability, both usually without knowing that used devices were being provided. The device company also bears additional liability. In addition, reused devices that perform poorly or are more prone to failure still have the manufacturer's name on them, damaging its reputation.
Some single-use devices include circuitry to detect whether the device has been used and will disable the device when a use has been detected. Other devices, such as that disclosed in U.S. Pat. No. 7,045,557, include a weak link such that the device will stand up to extended one time use, but will degrade quickly and obviously afterwards. Alternatively, some devices are designed such that the geometry of the device makes the device more difficult to properly clean and reprocess.
However, existing devices that employ the single use methods discussed above still can suffer from the above-mentioned problems associated with reprocessing.
Therefore, in view of the above-mentioned problems associated with reusing/reprocessing single-use electronic apparatus, it is desirable to develop a way of effectively disabling a single-use electronic apparatus in an efficient and cost effective manner.